Isocentric fixed angle irradiation-based DRR: a novel approach to enhance x-ray and CT image registration.

Digitally reconstructed radiography (DRR) plays an important role in the registration of intraoperative x-ray and preoperative CT images. However, existing DRR algorithms often neglect the critical isocentric fixed angle irradiation (IFAI) principle in C-arm imaging, resulting in inaccurate simulation of x-ray images. This limitation degrades registration algorithms relying on DRR image libraries or employing DRR images (DRRs) to train neural network models.

A study of balloon type on calcified coronary lesion predilation: A finite element analysis.

Calcified coronary lesions have been one of the more difficult types of lesion for interventional treatment, and angioplasty is required to break the calcification before stent implantation so that the stent can expand smoothly, however, it remains unclear which type of angioplasty is optimal for different calcified lesions. In this study, a finite element approach was used to model normal balloons, cutting balloons, and AngioSculpt balloons. In addition, calcified lesions of different degrees, thicknesses, and lengths were modeled according to Intravascular ultrasound (IVUS) calcification grade.

Influence of different postballoon expansion procedures: A finite element analysis.

Background: Postballoon expansion is considered as an appropriate procedure for adequate stent expansion for coronary bifurcation lesions. Two postballoon expansion procedures are currently recommended: proximal optimization technique (POT)/side/POT and POT/kiss/POT. However, the effects of the two postballoon expansion treatments are different.

Influence of balloon location during proximal optimization technique (POT): A finite element analysis.

Proximal Optimization Technique (POT)is a post-expansion technique that must be completed after single-stent implantation for the coronary bifurcation. The optimal location for the distal balloon shoulder during POT remains debatable. In the present study, the finite element method is applied to simulate POT after single-stent implantation in the coronary bifurcation.

Quantitative Evaluation of Coronary Plaque Progression by Computed Tomographic Angiography.

Understanding plaque formation in patients at risk for coronary artery disease-the leading cause of morbidity and death in the world-enables physicians to better determine whether and how to treat these individuals. We used computed tomographic angiography to quantitatively evaluate the progression of nonculprit coronary plaques along the full length of the right coronary artery in 21 patients with acute coronary syndrome. Each right coronary artery was analyzed in sequential, 3-mm-long segments, and the minimum luminal area, plaque burden, and plaque volume within each segment were evaluated at baseline and at 12-month follow-up.

Prediction of coronary plaque progression using biomechanical factors and vascular characteristics based on computed tomography angiography.

Objectives: Coronary atherosclerotic plaques progress in a highly individual manner. Accurately predicting plaque progression will promote clinical management of atherosclerosis. The purpose of this study was to investigate the role of local biomechanics factors and vascular characteristics in coronary plaque progression and arterial remodeling.

An automatic and accurate registration method for electro-anatomical map and CT surface.

Background: Electro-anatomical maps (EAM) and CT surface registration are widely used for catheter navigation in atrial fibrillation ablations. However, few studies have investigated the registration algorithm. Moreover, some of them are semiautomatic, so that physicians must be proficient; some are inaccurate for catheter navigation.

Preclinical Study of Anticoagulation Regimens in Sheep After Implantation of CH-VAD Blood Pump.

Effective anticoagulation regimens are needed to reduce risks of thrombosis and bleeding in animal models of ventricular assist device to verify its hemocompatibility, biologic safety and reliability. This study is to develop a validated anticoagulation procedure for a sheep model to test the newly developed CH-VAD. CH-VAD models were established in six healthy sheep by constructing blood bypass of left ventricle → ventricular assist device → descending aorta.

Initial In Vivo Evaluation of a Novel Left Ventricular Assist Device.

The aim of the study was to use the ovine model to evaluate the hemocompatibility and end-organ effects of a newly developed magnetic suspension centrifugal left ventricular assist device (LVAD) by CH Biomedical Inc., Jiangsu, China. The LVADs were implanted in 6 healthy sheep, where inflow was inserted into the left ventricular apex and outflow was anastomosed to the descending aorta.

In vivo evaluation of an implantable magnetic suspending left ventricular assist device.

Purpose: The CH-VAD is an implantable, fully magnetically suspended ventricular assist device developed by the China Heart Biomedical Corporation (Suzhou, China) for full cardiac support. This study was performed to evaluate the reliability, hemocompatibility and end-organ effects of CH-VAD in a 35-day animal model trial.

Methods: The pump was implanted in 6 sheep.

Evaluation of the impact of passive smoke on arterial elasticity via echo-tracking technology in a rabbit model.

Objectives: The purpose of this study was to evaluate the elasticity of the abdominal aorta in passively smoking rabbits using echo-tracking technology and pathologic examination.

Methods: Fifty-four male New Zealand White rabbits were randomly divided into a passive smoking group and a normal control group. The elasticity indicators for the abdominal aorta of the rabbits were measured by means of echo tracking, which was performed before and 1, 2, and 3 months after passive smoking.

Three new species of the tribe Meconematini (Orthoptera: Tettigoniidae) from Taiwan.

The paper reported three new species from Taiwan, i.e. Xizicus (Eoxizicus) taiwanensis sp.

Development and evaluation of a computerized Mandarin speech test system in China.

Objectives: This study reports the development and evaluation of a Computerized Mandarin Speech Test System (CMSTS).

Methods: Taking into account the rules for developing speech materials and the unique linguistic characteristics of Mandarin, we designed and digitally recorded a set of materials comprised of seven lists of monosyllabic words, nine lists of disyllabic words, and fifteen lists of sentences with a high degree of subject familiarity. The CMSTS was developed with Visual Studio 2008, Access 2003 and DirectX 9.

[Evaluation of right ventricular function of patients with intraoperative device closure of atrial septal defect by ultrasonic Doppler tissue imaging].

Objective: To study the application of Doppler tissue imaging (TDI) in the assessment of right ventricular function of patients with intraoperative device closure of atrial septal defect (ASD).

Methods: A total of 48 ASD patients, 18 males and 30 females, were selected for intraoperative device closure. The mean age was 31 +/- 16 years old.

[Application of transesophageal echocardiography in intraoperative device closure of secundum atrial septal defects].

Objective: To evaluate the clinical value of transesophageal echocardiography (TEE) in guiding intraoperative device closure of secundum atrial septal defect (ASD).

Methods: Fifty ASD patients, aged 40 +/- 18 (15-72), 34 with an ASD ranging from 30 to 40 mm and 16 with atrial septal aneurysm accompanied by double or more ASDs, underwent intraoperative device closure through a right minithoracotomy without cardiopulmonary bypass and fluoroscopy. Under general anesthesia, a probe was inserted into the esophagus, and TEE was conducted at different planes to observe the characteristics of the ASD.

[Studies on the blood compatibility of the polyurethane/nano-sized carbon composite].

Objective: To investigate the effects of nano-sized carbon as a dispersed phase on blood compatibility of polyurethanes.

Methods: A novel nanoscale polymeric composite film was prepared by dispersing nano-sized carbon fiber (vapor growth carbon fiber) into the polyurethane solutions. The surface blood compatibilities of the composites were analyzed and evaluated through platelet adhesion measurement using epifluorescent video microscopy and the variation of fibrinogen and free hemoglobin concentration in the blood contacting the composite respectively.

[Hemolysis test of the five kinds of impeller blood pumps in vitro].

Hemolysis caused by blood pumps is a very important characteristic. In vitro hemolysis test circuits were constructed to operate the model I centrifugal pump, the model II axial flow pump, the magnetic coupling pump and the model I & II spiral mixed pump. The output of all pumps was set at flow 5 L/min, an average pressure of 100 mmHg.

[Experimental study on effects of self-made miniature axial flow blood pump as left ventricle assistance for postischemic heart].

Objective: To evaluate the effects of self-made miniature axial flow blood pump as left ventricle assistance for postischemic heart.

Methods: Sixteen adult healthy sheep were divided into two groups of 8 sheep. After acute left heart failure was induced by selective ligation of the left anterior descending branch of coronary artery for 1.